The present invention relates generally to wall forms of the type comprising pairs of opposed form walls each formed of a plurality of stacked rows of plastic foam panels for receiving flowable materials such as concrete. More particularly, it relates to connectors used to maintain said form walls in spaced and parallel relationship.
A number of different systems and methods currently exist for making insulating forms for casting a concrete wall. Often, these systems comprise pairs of opposed foam panels generally made of a rigid foam like polystyrene which define concrete-receiving cavities therebetween. Once the concrete is solidified, the form walls remain in place to insulate the wall. Those form walls are typically maintained in spaced and parallel relationship before the pouring of concrete by means of connectors comprising a pair of parallel lateral attachment flanges each embedded in one of the two opposed foam panels, and a connecting web interconnecting the flanges.
Known concrete forms with the desirable rigidity are conventionally manufactured in the factory and are then shipped on the site of construction to be installed onto the ground to be treated with the inherent risk of damage during transportation or installation, particularly, since known pre-assembled form walls are fragile due to the important empty volume existing between the form walls.
In other conventional methods, forms satisfying the requirements of rigidity are installed directly on the site. However, they are complex and expensive, since the numerous components of the latter forms render assembly time consuming.
The following documents disclose examples of different prior art concrete forming systems: U.S. Pat. Nos. 5,459,971; 5,625,989; 5,709,060; 5,704,180; 5,701,710; 4,730,422; 5,065,561; 5,740,648; 5,657,600.
There is still presently a need for a wall form that will be easy to handle, to ship and to install on the site of construction and that will be low in cost.
An object of the present invention is to propose a wall form assembly that will satisfy the above-mentioned need, and more particularly to propose connectors therefor which overcome the drawbacks of the presently available methods and apparatus for making wall forms.
A further object is to provide a wall form which can be completely pre-assembled at the factory and which is as easy to transport to the site of construction as disassembled prior art wall forms.
In accordance with the present invention, these objects are achieved with a connector for tying together opposed foam panels in spaced and parallel relationship to make a form for receiving flowable material. The connector comprises a pair of anchor members, one being devised to be embedded in one of the foam panels and the other being devised to be embedded in the other one of the foam panels. Each anchor member has an elongated flange plate for extending longitudinally and deep inside the foam panel and an elongated link element connected longitudinally to the flange plate and having a projecting end devised to come out of the foam panel once the anchor member is embedded therein. The connector further comprises a web member for extending between the foam panels, the web member having opposite longitudinal side ends, each of the side ends being hingedly connectable to the projecting end of either one of the anchor members, whereby the foam panels are tied together by connecting one side end of the web member to the projecting end of one of the anchor members and the other side end of the web member to the projecting end of the other anchor member. Thus, the tied foam panels are movable between an extended position where the foam panels are spaced-apart to make the form and a collapsed position where the foam panels are brought close to each other.
Preferably, the projecting end of each anchor member comprises a stabilising plate parallel to the flange plate for extending flush with an inner surface of the foam panel.
In a first preferred embodiment, a plurality of aligned open slotted tube-like knuckles are disposed on the stabilising plate. Each tube-like knuckle forms an inner tube having a pair of longitudinal opposed edge portions defining a slot in registry with the slots of the other knuckles. In this case, each longitudinal side end of the web member defines an enlarged end portion sized to be slidingly insertable in the open tube-like knuckles and a strip portion connecting the enlarged end portion to a central portion of the web member. The strip portion has a width sized so the strip portion is slidingly insertable in the slots of the anchor members and includes a plurality of aligned slits each adapted to receive an edge portion of the knuckles, thereby allowing the web member and the anchor member to pivot with respect to each other.
In a second preferred embodiment, the projecting end of each anchor member has a plurality of connecting elements disposed on the stabilising plate. Each connecting element comprises a longitudinally extending pivot pin. The web member has opposite longitudinal side ends, each of the longitudinal side ends defines a plurality of arms cooperating with each of the connecting elements, each arm having an extremity pivotally connected to the pivot pin of a corresponding connecting element so as to be rotatable around an axis defined by said pivot pin, thereby allowing the web member and anchor member to pivot with respect to each other.
The present invention is also directed to a wall form assembly comprising opposed foam panels disposed in spaced and parallel relationship to make a form for receiving a flowable material such as concrete and a plurality of connectors as described above tying the opposed foam panels together. More particularly, the form wall assembly comprises:
a first and a second opposed foam panels in spaced and parallel relationship; and
a plurality of connectors tying together the first and second foam panels, each connector comprising:
a pair of anchor members, a first one embedded in the first foam panel and the second one embedded in the second foam panel, each anchor member having:
an elongated flange plate extending longitudinally and deep inside the foam panel; and an elongated link element connected longitudinally to the flange plate and having a projecting end coming out of the foam panel, and
a web member extending between said foam panels, the web member having a first longitudinal side end opposite a second longitudinal side end, said first longitudinal side end being hingedly connected to the projecting end of the first anchor member and the second longitudinal side end being hingedly connected to the projecting end of the second web member;
whereby the tied foam panels are movable between an extended position where the foam panels are spaced-apart to make the form and a collapsed position where the foam panels are brought close to each other.
A wall form assembly according to the present invention can be easily manufactured, compacted and stored without requiring a lot of space or transported to the site of construction. Due to the relatively light weight of the material used for the manufacture of the elements of the wall form assembly and due to the fact that these elements can be packed in a compact form, a wall form assembly according to the present invention is a lot less fragile during shipping than prior art pre-assembled wall forms, the freight costs for transportation are significantly reduced and the time required to install the form on the site is also significantly reduced as the form is already assembled.
Other features and objects of the present invention will become more apparent from the description that follows of preferred embodiments thereof, having reference to the appended drawings and given as examples only as to how the invention may be put into practice.